#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int main()
{
    int a = 0, int b = 0, int c = 0;
    scanf("%d %d %d", &a, &b, &c);
    if (a + b > c && b + c > a && b + c > a)
    {
        if (a == b && a == c)
            printf("Equilateral triangle!");
        else if (a == b || a == c || b == c)
            printf("Isosceles triangle!");
        else
            printf("Ordinary triangle!");
    }
    else
        printf("Not a triangle!");
    return 0;
}